*{
    margin: 0;
    padding:0;
    text-decoration: none;
    list-style: none;
}

.container{
    width: 1000px;
    height: 600px;
    font-size: 0;
    margin: 30px;
}
.left-img{
    width: 490px;
    height: 510px;
    display: inline-block;
    border: 1px solid #eee;
    margin-right: 16px;
    background-image: url(./images/imgA_2.jpg);
    background-repeat: no-repeat;
    background-position: center;
    background-size: cover;
    position: relative;
}
.mask{
    position: absolute;
    top:0;
    left:0;
    opacity: 0;
    width:230px;
    height: 230px;
    background-image: url(./images/bg.png);
    
}
.right-img{
    width: 490px;
    height: 510px;
    display: inline-block;
    border: 1px solid #eee;
    background-image: url(./images/imgA_3.jpg);
    background-position: center;
    background-repeat: no-repeat;
    opacity: 0;
}
.img-list-wrapper{
    width: 490px;
    margin-top: 10px;
    text-align: center;

}
.img-list{
   display: inline-block;
}
.img-list li{
    display: inline-block;
    width:60px;
    height: 60px;
    border: 1px solid #eee;
    margin:0 5px;
    /* background-image: url(./images//imgA_1.jpg); */
    background-repeat: no-repeat;
    cursor: pointer;
}